and the big question then becomes what is china's intention? (instrumental music) >> in a national call to arms defense secretary leon panetta warned the threat of a significant cyber attack against america is already here. >> the collective result of these kinds of attacks could be a cyber pearl harbor. >> what are the threats american's face in this century? with the attacks of september 11th, the u.s. has had to completely rethink how it defends its citizens. the enemy no longer a national armies but rather determined individuals. >> there are not going to be a lot of countries that are gonna be stupid enough to put tank armies out in the desert against us anymore to allow us to annihilate them. what the lessons of history of the last twenty years or so certainly teach us is that if you're fight us, you can have greater success by using terrorist tactics, by employing suicide bombers, i.e.d.'s, those kinds of attacks. >> that was probably the biggest impact on national security. we have non-nation state actors that can cause harm to the unit